First and foremost, the largest single thing anyone can do to be eco friendly is to adopt a plant-based diet. Animal agriculture is the single largest source of green house gases, soil erosion, water pollution, deforestation, and loss of native species.
Assuming that You weight 110 lbs ( 50 kg) , don't do any heavy physical work or intensive sport
YES - then You can eat 7 kilograms of veggies a day , but people evolved to EAT EVERYTHING
so proteins and fat is really necessary for normal development